Type-writing machine.



B. P. FORTIN i G. H. HORTON.

.TYPE WRITING MACHINE.

APPLIoA'rIoN FILED AUG. 1a, 1910.

Bam-,ea septk 5,' 1911.

UNITED STATES `PATENT OFFICE.

BENJAMIN l?. FORTIN AND GEORGE I-I. HOB/TON, OF HARTFORD; CONNECTICUT, .ASSIGN- ORS TO UNDERWOOD TYPEWRITER COMPANY, OF NEW YORK, N. Y.; A CORPORATION OF DELAWARE.

TYPE-WRITING MACHINE.

Specification of Letters Patent.

Patented sept. 5, 1911.

To all whom it may concern.'

Be it known that we, BENJAMIN P. Fon- TIN and GEORGE I-I. HoR'roN, both citizens of the United States, and residing in the city of Hartford, county of Hartford, and State of Connecticut, have invented certain new and useful Improvements in Type-Writing Machines, of which the following is a specifcation.

This invention relates to line-space mech anisms for typewriting machines, and more particularly to means to turn the platen backwardly part of a line-space to print exponents, fractions, accents, ete.

According to the present invention, a finger lever forces a dog (pivoted independently of the lever) to engage and turn the usual line-space wheel. The dog seats between the teeth of the line-space wheel in a manner to lock the platen against overthrow.

In the accompanying drawings, Figure 1 is a perspective of the invention applied to an Underwood writing machine. Fig. 2 is an end view, showing the device in normal idle position. Fig. 3 shows the parts in effective positions. Fig. 4 is a plan of the mechanism.

Types 1 strike a platen 2, fast on an axle 3 journaled in the ends 4 of a platen frame. The platen is line-spaced by a lever 5, through a slide 6 and pawl 7, the latter engaging a toothed or notched wheel 8, fast on the axle 3, and held against accidental rotation by a detent 9, pivoted at 10 to the platen frame end 4. Depression of the forward key-bearing arm 11 of a lever 11, 12, pivoted intermediate its ends, preferably on the axle 3, presses a linger 15, formed on the rear arm l2, against a dog 13 rocking on the pivot 10. A dog tooth 14 strikes between any two adjacent teeth of the linespace wheel 8, and turns the wheel and platen part of a line-space backwardly, to enable the printing of characters above the usual writing line. A stop 16 on the dog strikes the detent 9, to be arrested thereby, and hence the dog is rigidly supported and enabled to arrest the platen positively, without liability of springing of the parts; the tooth 14 being made of suflicient width to fill the space between adjacent teeth of the lineespace wheel. A spring 17 disengages the tooth 14 from the wheel and returns the f dog 13 and lever 11, 12 to idle positions.

The spring 17 in disengaging the tooth presses it against the rear wheel tooth, to start the line-space wheel and platen toward initial positions, such starting of t-he linespace wheel letting the detent ride olf from the point of the wheel tooth, so that the seating of the detent in the notch from which it was cammed when the platen was turned by the lever 11, may complete the return of the platen to initial position.

Having thus described our invention, we claim:

1. In a typewriting machine, the combination with a platen and a notched linespaee wheel connected thereto, of a linger lever, a dog pivoted independently thereof and having a tooth which is rocked into any notch in the wheel by the finger lever to turn the platen part of a line-space, and a stop to arrest the dog and platen before the latter has turned a line-space, the tooth fitting in any notch in the wheel to lock the platen against overthrow, and constructed upon its return movement to start the linespace wheel and platen toward their initial positions.

2. In a typewriting machine, the combination with a platen and its axle, regular line-space mechanism therefor including a toothed wheel fast on the axle, and a detent engaging the wheel, of an exponent device comprising a dog pivoted independently of the axle, one arm of the dog having a tooth, a lever pivoted on the axle and engaging the dog to throw the tooth into engagement with the wheel and turn the platen part of a line-space, a stop on the other arm of the dog to strike the detent to arrest the platen, and a returning spring to disengage the tooth from the wheel, the tooth of the dog being of such shape as to fit between any two teeth of the wheel to start the wheel toward its initial position, as the tooth is disengaged.

3. In a typewriting machine, the combination with a platen and its axle, linespace mechanism therefor, including a notched wheel fast on the axle, of an exponent device comprising a dog pivoted in dependently of the axle, a tooth on the dog to fit between any two adjacent-'teeth of the wheel, a lever pivoted on the axle to press the tooth into the wheel and turn the platen part of a line-space, and a stop to arrest the dog and platen.

4. In a typewriting machine, the combination With a platen, a notched line-space' Wheel connected thereto, and a springpressed detent for said line-space Wheel, of a dog enga-geable With said line-space Wheel to turn the same about half a line-space, whereby said detent is moved to a position upon the tip of a Wheel tooth; means cooperating with saiddog to arrest the linespace Wheel in such position; and saidv dog- Copies of this patent may be obtained for ve cents eachpby addressing the Commissioner of Patents,

Washington, D. C. 

